In recent years the use of polymer based dental materials has gained in prominence, since these materials have improved physical and mechanical properties and provide dental restorations having superior durability. These materials have been found to be particularly useful as filled restorative materials, bonding agents, tissue scalers and orthodontic adhesives, particularly those materials based upon polymerizable aromatic and aliphatic methacrylates, which polymerize in situ, most with the application of visual light.
The best properties in these types of materials have been obtained when the resin part of the composition is comprised of one or more of the following monomers: ##STR3## 2,2-bis-[4'-(3"-methacroyl-2"-hydroxypropoxy)-phenyl]propan, known in industry as BIS-GMA, its adduct with various alkyl iso, or diisocyanates, such as the adduct described in Waller U.S. Pat. No. 3,629,187 and urethane dimethacrylates as are described, for example, in the U.S. Pat. Nos. 3,425,988; 3,709,866 and 3,629,187 and the like; and ##STR4## i.e. 2,2-bis(4'(2"-methacroylethoxy)phenyl)propane, known in industry as EBA.
In addition to the aforementioned references various polymeric dental materials have been described in the following U.S. Pat. Nos.: 3,066,112 (Bowen); 3,179,623 (Bowen); 3,194,783 (Bowen); 3,194,784 (Bowen); 3,539,533 (Lee II et al.); 3,541,068 (Taylor); 3,597,389 (Taylor); 3,721,644 (Stoffey et al.); 3,730,947 (Stoffey et al.); 3,751,399 (Lee Jr. et al.); 3,766,132 (Lee Jr. et al.); 3,774,305 (Stoffey et al.); 3,860,556 (Taylor); 3,862,920 (Foster et al.); 3,926,906 (Lee II et al.); 4,102,856 (Lee Jr.); 4,107,845 (Lee Jr. et al.); 4,490,115 (Orlowsky et al.); 4,544,359 (Waknine); 4,536,523 (Antonucci); 4,551,486 (Tateosian); 4,552,906 (Podszun); 4,553,940 (Koblitz et al.).